/**
 * Copyright 2011-2013 FoundationDB, LLC
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *     http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/* The original from which this derives bore the following: */

/*

   Derby - Class org.apache.derby.impl.sql.compile.BinaryOperatorNode

   Licensed to the Apache Software Foundation (ASF) under one or more
   contributor license agreements.  See the NOTICE file distributed with
   this work for additional information regarding copyright ownership.
   The ASF licenses this file to you under the Apache License, Version 2.0
   (the "License"); you may not use this file except in compliance with
   the License.  You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

 */

package com.bj58.sql.parser;

import com.bj58.sql.StandardException;
import com.bj58.sql.types.ValueClassName;

/**
 * A BinaryOperatorNode represents a built-in binary operator as defined by
 * the ANSI/ISO SQL standard.    This covers operators like +, -, *, /, =, <, etc.
 * Java operators are not represented here: the JSQL language allows Java
 * methods to be called from expressions, but not Java operators.
 *
 */

public class BinaryOperatorNode extends ValueNode
{
    protected String operator;
    protected String methodName;

    public static enum OperatorType {
        PLUS, MINUS, TIMES, DIVIDE, CONCATENATE, MOD, DIV,
        EQ, NE, GT, GE, LT, LE, AND, OR, LIKE, LTRIM, TRIM, RTRIM,
        BITAND, BITOR, BITXOR, LEFT_SHIFT, RIGHT_SHIFT,
        LEFT, RIGHT
    }

    protected ValueNode leftOperand;
    protected ValueNode rightOperand;

    protected String leftInterfaceType;
    protected String rightInterfaceType;
    protected String resultInterfaceType;

    /**
     * Initializer for a BinaryOperatorNode
     *
     * @param leftOperand The left operand of the node
     * @param rightOperand The right operand of the node
     * @param operator The name of the operator
     * @param methodName The name of the method to call for this operator
     * @param leftInterfaceType The name of the interface for the left operand
     * @param rightInterfaceType The name of the interface for the right operand
     */

    public void init(Object leftOperand, Object rightOperand,
                     Object operator, Object methodName,
                     Object leftInterfaceType, Object rightInterfaceType) {
        this.leftOperand = (ValueNode)leftOperand;
        this.rightOperand = (ValueNode)rightOperand;
        this.operator = (String)operator;
        this.methodName = (String)methodName;
        this.leftInterfaceType = (String)leftInterfaceType;
        this.rightInterfaceType = (String)rightInterfaceType;
    }

    public void init(Object leftOperand, Object rightOperand, 
                     Object leftInterfaceType, Object rightInterfaceType) {
        this.leftOperand = (ValueNode)leftOperand;
        this.rightOperand = (ValueNode)rightOperand;
        this.leftInterfaceType = (String)leftInterfaceType;
        this.rightInterfaceType = (String)rightInterfaceType;
    }

    /**
     * Fill this node with a deep copy of the given node.
     */
    public void copyFrom(QueryTreeNode node) throws StandardException {
        super.copyFrom(node);

        BinaryOperatorNode other = (BinaryOperatorNode)node;
        this.operator = other.operator;
        this.methodName = other.methodName;
        this.leftOperand = (ValueNode)
            getNodeFactory().copyNode(other.leftOperand, getParserContext());
        this.rightOperand = (ValueNode)
            getNodeFactory().copyNode(other.rightOperand, getParserContext());
        this.leftInterfaceType = other.leftInterfaceType;
        this.rightInterfaceType = other.rightInterfaceType;
        this.resultInterfaceType = other.resultInterfaceType;
    }

    /**
     * Convert this object to a String.  See comments in QueryTreeNode.java
     * for how this should be done for tree printing.
     *
     * @return This object as a String
     */

    public String toString() {
        return "operator: " + operator + "\n" +
            "methodName: " + methodName + "\n" + 
            super.toString();
    }

    /**
     * Set the operator.
     *
     * @param operator The operator.
     */
    void setOperator(String operator) {
        this.operator = operator;
    }

    public String getOperator() {
        return operator;
    }

    /**
     * Set the methodName.
     *
     * @param methodName The methodName.
     */
    void setMethodName(String methodName) {
        this.methodName = methodName;
    }

    public String getMethodName() {
        return methodName;
    }

    /**
     * Set the interface type for the left and right arguments.
     * Used when we don't know the interface type until
     * later in binding.
     */
    public void setLeftRightInterfaceType(String iType) {
        leftInterfaceType = iType;
        rightInterfaceType = iType;
    }

    /**
     * Prints the sub-nodes of this object.  See QueryTreeNode.java for
     * how tree printing is supposed to work.
     *
     * @param depth The depth of this node in the tree
     */

    public void printSubNodes(int depth) {
        super.printSubNodes(depth);

        if (leftOperand != null) {
            printLabel(depth, "leftOperand: ");
            leftOperand.treePrint(depth + 1);
        }

        if (rightOperand != null) {
            printLabel(depth, "rightOperand: ");
            rightOperand.treePrint(depth + 1);
        }
    }

    /**
     * Set the leftOperand to the specified ValueNode
     *
     * @param newLeftOperand The new leftOperand
     */
    public void setLeftOperand(ValueNode newLeftOperand) {
        leftOperand = newLeftOperand;
    }

    /**
     * Get the leftOperand
     *
     * @return The current leftOperand.
     */
    public ValueNode getLeftOperand() {
        return leftOperand;
    }

    /**
     * Set the rightOperand to the specified ValueNode
     *
     * @param newRightOperand The new rightOperand
     */
    public void setRightOperand(ValueNode newRightOperand) {
        rightOperand = newRightOperand;
    }

    /**
     * Get the rightOperand
     *
     * @return The current rightOperand.
     */
    public ValueNode getRightOperand() {
        return rightOperand;
    }

    /**
     * Return whether or not this expression tree represents a constant expression.
     *
     * @return Whether or not this expression tree represents a constant expression.
     */
    public boolean isConstantExpression() {
        return (leftOperand.isConstantExpression() &&
                rightOperand.isConstantExpression());
    }

    /**
     * Accept the visitor for all visitable children of this node.
     * 
     * @param v the visitor
     *
     * @exception StandardException on error
     */
    void acceptChildren(Visitor v) throws StandardException {
        super.acceptChildren(v);

        if (leftOperand != null) {
            leftOperand = (ValueNode)leftOperand.accept(v);
        }

        if (rightOperand != null) {
            rightOperand = (ValueNode)rightOperand.accept(v);
        }
    }

    /**
     * @inheritDoc
     */
    protected boolean isEquivalent(ValueNode o) throws StandardException {
        if (!isSameNodeType(o)) {
            return false;
        }
        BinaryOperatorNode other = (BinaryOperatorNode)o;
        return methodName.equals(other.methodName) && 
            leftOperand.isEquivalent(other.leftOperand) && 
            rightOperand.isEquivalent(other.rightOperand);
    }

}
